The counter QR with a free-drink reward is the classic setup: people are already waiting, and the reward costs you a marginal pour. Evergreen questions: what brought them in, how today compared to what they wanted, the closing satisfaction score. Ad-hoc: whatever you’re actually deciding — the new pastry case, weekend hours, the oat-milk brand.
Expect short, concrete answers — that’s the point. Ten real answers about today’s service beat a hundred star-ratings from last month.